When you are researching your German ancestors don’t forget to mine all the resources from the towns they lived in. Perhaps before they settled someplace permanently they lived in several states and there were major life events that happened in that town. Marriages, births, deaths or maybe just a mention in the local paper, these are all things you need to check out for the mention of a past hometown in Germany.
Your first objective is to find them in every U.S. and State census since they arrived in the country. This will show you all the places they lived and give you the town, county and state. (Find census images at Ancestry.com or your local library may have a subscription to Ancestry or Heritage Quest, also FamilySearch.org has free access to US census records). I would then do a Google search for the town’s local Historical Society or Genealogy Society and see what is available on their website. A lot of these societies are putting indexes and even some documents online. They also give information on local resources, perhaps where the vital records are kept, or links to other resources in the area. These societies also have a wealth of information that probably is not online. For years people have donated their time to index local records or the people that volunteer there have lived in that town all their life and know many family names. It is worth the time to contact them.
You may try your local library. Do they have a genealogy section? Maybe you live near a larger library that does. These institutions may have collected books or microfilms from other states and counties that are genealogy related and you can find what you are looking for close to your home.
Another great find is to do some searching on Google Books. I did some searching for Germans in Ohio, and found some great books available on line to read. One was Franklin County, Ohio history, which gives the founding of the county plus early settlers and hometowns. So I suggest playing at this site with family names, county names, German immigration etc. You may have a fantastic find.
The internet makes it easy for us to travel the world from our living room but you also must remember to look for printed items that are not on the internet yet. You need to work the town they lived in for all possible resources. Good luck!